Pat. No. 4,853,325 describes a saliva test for FeLV. That test employs a probe having an immunochemically sensitive member for collecting saliva from the oral cavity of a cat and employs ELISA reagents for the incubation of the probe and the development of color reactions to indicate the presence or absence of FeLV within the saliva sample collected onto the probe.
The probe, wetted with cat saliva, is then incubated in an incubation vessel containing an enzyme conjugate of anti-FeLV antibodies in a solvent or diluent. Typical conjugate diluents include buffers such as phosphate, borate or carbonate; protein stabilizers such as bovine serum albumin (BSA), casein or gelatin; surfactants such as polyoxyethylene alcohols, polyoxyethylene fatty acid esters or alkylaryl polyether alcohols. The concentration of the conjugate in the diluent may lie from about 0.1 .mu.g/mL (microgram per milliliter) to about 10.0 .mu.g/mL. Unbound conjugate is removed. The bound conjugate which remains on the probe allows the immunologically sensitive member to be color developed. Color development indicates that FeLV and FeLV antigens were present in the saliva sample.
The specificity of this test is sometimes compromised by excessive nonspecific background and by false positives.